Hozelock Spray and Feed

Hozelock are market leaders in hosepipes and accessories for watering gardens but wanted to grow their business in the fertilising market. The main players in this market like Scott’s Miracle Gro and Levington are chemicals businesses who make occasional accessories to help apply their own products. From a product perspective there wasn’t much overlap between the two.

The problem facing the gardener is that they would need a different accessory depending on which type of fertiliser they wanted to use i.e. Tomorite or Miracle gro. This is inconvenient and meant that the typically traditional gardening customer would stick with the old-fashioned method of mixing feed in a watering can and lugging the heavy weight around the garden.

A better solution would be a lightweight reusable product that could easily be attached to the end of a hosepipe and would work with everyone else’s chemicals.

Step 1: Define the problem by understanding the challenge.

It wasn’t as if hose end mixing of fertiliser and water needed inventing since the chemical makers were already doing that. However, the problem was that each product was dedicated to its own chemical and there was also evidence to suggest that the concentration of the feed to the water wasn’t very well controlled – perhaps because these products were designed by chemicals businesses as opposed to watering businesses.

The water pressure in a garden hose pipe is unpredictable and ranges widely not only due to mains pressure variation but the user also has control of the tap. These variations when combined with some simple methods of mixing developed by the chemicals businesses meant that the gardener could easily over feed the garden which is detrimental to plant growth.

What was needed was a device that would automatically compensate for changes in the water flow rate as well as changes in the viscosity of the fertiliser.

Step 2: Solving the problem by looking in the patent archive.

We don’t believe in invention for inventions sake. It is often the case in mechanical consumer products but the basic technical building blocks of what you are looking for have already been provided by generations of engineers that have gone before. Often here in the 21st century we are only doing what the Victorians could have done but with a twist of new materials, new processes and the needs of the modern customer. So, we undertook a survey of mixing methods that were published in the worldwide patent archive and struck gold. Back in the middle of the last century a German engineer had perfected and patented a method of lubricating machinery by adding a chemical to the hydraulic fluid as is as pumped around the machine.

Step 3: The solution by delivering easy control

The basic method was to use the pressure drop present in any flowing liquid to drive an offline piston which was full of the chemical that was to be mixed into the flow. This technology gave us a foundation on which to build a solution. The challenge we solved was how to give the user control of concentration irrespective of changes in water flow but also to changes in the viscosity of chemical.

The next step was to take this technical solution and present it in a form that would be easily understood by the end user as well as making sure it could be manufactured on high volume basis using injection moulded plastics and assembly methods.

Step 4: Results – a spray head that feeds

The final product is basically a combination of a standard hose sprayer with an option to feed at the touch of a button. In addition to the usual on/off and volume controls of a standard spray head there is a simple slider to turn on the feed which means that the product could stay on the end of the hosepipe permanently and be used for all watering and feeding tasks. Pushing the volume control quickly flushes the system and the type of feed can be quickly changed over by attaching a different cannister from the garden shed.